Phenoxyethyl n-phenyl-n-phenoxyethyl-piperazinylethylcarbamate

ABSTRACT

PHENOXYETHYL N-PHENYL-N-PHENOXYETHYLPIPERAZINYLETHYLCARBAMATE IS PREPARED IN GOOD YIELD BY REACTING AT AN ELEVATED TEMPERATURE AN APPROPRIATE N-HYDROCARBYLCARBAMATE WITH TRIETHYLENEDIAMINE OR AN N-HYDROCARBYLCARBAMATE, TRIETHYLENEDIAMINE. THE N-PIPERAZINYL DERIVATIVE SO-FORMED IS USEFUL AS CATALYSTS IN THE MANUFACTURE OF POLYURETHANES, IN THE PREPARATION OF ACID-SOLUBLE AND ACID-DYEABLE POLYURETHANES.

3,828,047 PHENOXYETHYL N-PHENYL-N-PHENOXYETHYL- PIPERAZINYLETHYLCARBAMATE Franklin W. Abbate, North Haven, and William J. Farrissey, Jr., Northford, 'Conn., assignors to The Upjohn Company, Kalamazoo, -Mich.

No Drawing. Original application Mar. 2, 1970, Ser. No. 15,925, now Patent No. 3,719,680, dated Mar. 6, 1973. Divided and this application Dec. 13, 1972, Ser. No.

Int. Cl. C07d 51/70 US. Cl. 260-268 R 1 Claim ABSTRACT OF THE DISCLOSURE Phenoxyethyl N phenyl-N-phenoxyethylpiperazinylethylcarbamate is prepared in good yield by reacting at an elevated temperature an appropriate N-hydrocarbylcarbamate with triethylenediamine or an N-hydrocarbyl- 'carbamate, triethylenediamine. The N-piperazinyl derivative so-formed is useful as catalysts in the manufacture of polyurethanes, in the preparation of acid-soluble and acid-dyeable polyurethanes.

CROSS REFERENCE TO RELATED APPLICATIONS This is a division of application Ser. No. 15,925, filed Mar. 2, 1970, now US. Pat. No. 3,719,680, issued Mar. 6, 1973.

. BACKGROUND OF THE INVENTION (1) Field of the Invention This invention relates to a novel N-(piperazinylethyl) carbamate and to a method for its preparation and relates particularly to phenoxyethyl N-phenyl-N-phenoxyethylpiperazinylethylcarbamate synthesized by reacting at an elevated temperature the appropriate N-hydrocarbylcarbamate with triethylenediamine.

(2) Description of the Prior Art The only work previously described in the art in which triethylenediamine has been employed as a reactant to give a piperazine derivative is that of Ross et al., JACS, 85, 3999 (1963) who reacted 2,4-dinitrochlorobenzene with triethylenediamine to form the compound:

N-oi SUMMARY OF THE INVENTION The present invention comprises a novel compound of the formula: 7 r

United States Patent 'ice diamine which is employed in substantial quantities in the urethane industry in foam preparation as well as in the manufacture of other urethane products. It has been found that the novel N-(piperazinylethyl)-carbamates of this invention are valuable urethane catalysts which may be employed as a substitute for a part or all of the triethylenediamine commonly utilized in the production of polyurethanes by interaction of diisocyanates and polyols or in the production of polyureas by interaction of diisocyanates and polyamines. Methods for producing such polyurethanes and polyureas in the form of film, fibers and foams utilizing the conventionally employed diisocyanates and polyols together with the novel catalysts of this invention will be readily apparent to those skilled in the art. Conventional procedures for the synthesis of such polyurethanes are described by Saunders et al., Polyurethanes, Chemistry and Technology, part II, Interscience Publishers, 1964, pp. 299-451.

Examples of art-recognized polyols which can be employed alone, or as mixtures, in preparing polyurethanes include the following:

(1) aliphatic diols, such as ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, 1,2-hexanediol, 1,5-pentanediol, 1,2-hexanediol, etc.;

(2) aliphatic triols, such as trimethylolmethane, trimethylolethane, 1,2,3-hexanetriol, 1,1,l-trimethylolhexane, etc.;

(3) aliphatic tetrols, such as erythritol, pentaerythritol,

etc.;

(4) aliphatic pentols, such as arabitol, xylitol, etc.;

(5) aliphatic hexols, such as mannitol, sorbitol, dipentaerythritol, etc.;

(6) aniline-alkylene oxide diol adducts;

and adducts prepared by reacting any of the above-named compounds (1) through (5) above with one or more molar proportions of ethylene oxide, propylene oxide, 1,2-butylene oxide, or mixtures thereof.

Any of the prior art polyisocyanates can be used as reactants in preparing polyurethane products when utilizing the novel product of this invention as catalyst e.g., 2,4- tolylene diisocyanate, 2,6 tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, dianisidine diisocyanate, tolidine diisocyanate, hexamethylene diisocyanate, m-xylene diisocyanate, 1,5-naphthalene diisocyanate, and other diand higher polyisocyanates such as those listed in the table of Siefken, Ann., 562, 122-135 (1949). Preferred polyisocyanates, however, are products obtained by phosgenation of mixtures of methylene-bridged polyphenyl polyamines obtained by the interaction of formaldehyde, hydrochloric acid, and primary aromatic amines, for example, aniline, o-chloroaniline, o-toluidine, or mixtures thereof. Such polyisocyanates are known in the art, e.g., US. Pat. Nos. 2,683,730; 2,950,263; and 3,012,008; Canadian Pat. No. 665,494; and German specification 1,131,877.

In preparing polyurethane products employing the novel N-(piperazinylethyl)-carbamates of this invention as catalysts, or as a part of the catalyst mixture, by reaction of any of the polyisocyanates conventionally employed in the art with the available polyols, blowing agents, surfactants cell-openers and the like adjuvants commonly employed for the production of polyurethane products may be used. If desired, special polyols such as the phosphoruscontaining polyols can be incorporated in the polyurethane reaction mixture in order to impart fire retardant properties to the resulting foam. Examples of such phosphoruscontaining polyols are the tris polypropylene glycol phosphates produced by interaction of phosphoric and propylene oxide as, for example, described in US. Pats. Nos. 2,372,244 and 3,094,549.

- DETAILED DESCRIPTION OF THE INVENTION The novel N- (piperazinylethyD-carbamate of" this invention is obtained by reacting at an elevated temperature phenoxyethyl N-phenylcarbarnate with triethylenediamine.

The process and product thereof can be illustratively represented as follows:

wherein R is phenyl and R is phenoxyethyl.

In conducting the foregoing process, the N-hydrocarbylcarbamate employed as a starting material is preferably reacted with triethylenediamine in the presence of an inert organic solvent. The inert organic solvent can be any organic solvent which is inert under the conditions of the reaction, c.g., does not enter into reaction with any of the reactants employed or in any way interfere with the progress of the reaction. Suitable inert organic solvents include benzene, toluene, xylene, naphthalene, Decalin, chlorobenzene, o dichlorobenzene, bromobenzene, etc.

Advantageously, processes (a) and (b) are conducted at a temperature ranging from about 80 to about 300 C. and preferably at a temperature within the range of about 125 C. to about 200 C. Approximately stoichiornetric quantities of the reactants are generally employed in the process although if desired, an excess of the carbamate can be utilized. The progress of the conversion of the N-hydrocarbylcarbamate to the desired piperazine derivative can be followed by any of the appropriate analytical techniques such as infrared spectrographic analysis, etc. The desired N-(piperazinylethyl)-carbamate can be isolated from the reaction mixture by conventional procedures in organic chemical operations such as by extraction, distillation, precipitation as the hydrochloric acid salt, etc.

The phenoxyethyl N-phenylcarbamate utilized as a starting material is a known compound which can be prepared by methods conventional in the art for the preparation of N-substituted carbamates. A particularly convenient method involves the reaction of the appropriate chloroformate and appropriate hydrocarbylamine; see for example, H. von Pecbmann, Ber., 28, 855 1895 for a description of the preparation of ethyl N-methylcarbamate from methylamine and ethyl chloroformate as representative of the conditions required in preparing this compound. Another method for the preparation of the N-substituted carbamate involves the reaction of the corresponding N-substituted carbamyl halide with the appropriate alcohol for example, using the procedure described by Gattermann, Annalen, 244, 30 (1888) for the reaction of carbamyl chloride itself with alcohols.

N-substituted carbamates can also be obtained by the alkylation of olefins with urethane (ethyl carbamate) as described by Mueller and Merten, Ben, 98, 1097 (1965) A preferred embodiment of this invention is illustrated by the following example which is to be considered not limitative.

A total of 11.02 g. of-phenoxyethyl N-phenylcarbamaterandlt) g. of triethylenediaminewere-,refluxedrin ml. of chlorobenzene for;6 hours; 4;

Following dilution :of 'the reaction mixture-with: ether, it-was extracted with four portions of hydrochloric acid (5 percent by volume)and finally with"wa t'er. ln=thej next step the resulting aqueous, acid layer was washed with two portions vof ether. 'I'he organic-laye'ris were combined, washed with a saturated salt'solution and"finfallyjdried over magnesium sulfate and; after evaporatio'n of the ether, residue containing the unreacted stattipg' carba mate was obtained. I H T i The acid aqueous layer 'wasmade. basicthrough the addition of sodium hydroxide (10 percent 'by volume), saturated with sodium chloride and then" extracted with five portions of ether. After the ether phase had-.been washed to neutrality with a saturated saltsolution, it was dried over magnesium sulfate and on evaporation. there was recovered in good yield the compound having the formula: i

References- Cited v UNITED STATES PATENTS 3,121,213 4/1964 Surrey "1 266- 268 R 3,719,680 3/1973 Abbate et a1 260-268 R 3,721,674 3/1973 Abbate etal. 260-268 R DONALD o. DAUS, Primary Examiner UNITED STATES PATENT OFFICE CERTIFICATE CORRECTION I 3,828,047 August a, 1974 Patent No. Dated I Firanklin W, Abbate and William J; Farris sey, Jr. Inventofls) It is certified that error appears in the aboveddencifled patent and that said Letters Patent are :heg-eby corrected as shown below:

Col. 1, lines 18 a d 19: Should read:

triethylehediamineor an V I triethylenedi aminei N-hydrocarbylear'bamate, tri- Y The N-piperaz'inyl ethylenediamine. The N- r I piperazinyl Col. 1, lines 53' 160: v Should read: V v

"c 1. 2, line 56: Should read:

Patent No. 65, 49 I Patent No. 665,495

Signed and sealed this 19th dey of November 1974.

(SEAL) AtteSt: H I H McCOY M. GIBSON JR. 7 1 c. MARSHALL DANN Attesting Officer 7 Commissioner of Patents can 96-1050 (an-e5) 

